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/*
* Copyright (c) 2010, 2015 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
* Copyright (c) 2005 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "dev/arm/pl011.hh"
#include "base/trace.hh"
#include "debug/Checkpoint.hh"
#include "debug/Uart.hh"
#include "dev/arm/amba_device.hh"
#include "dev/arm/base_gic.hh"
#include "mem/packet.hh"
#include "mem/packet_access.hh"
#include "params/Pl011.hh"
#include "sim/sim_exit.hh"
namespace gem5
{
Pl011::Pl011(const Pl011Params &p)
: Uart(p, 0x1000),
intEvent([this]{ generateInterrupt(); }, name()),
control(0x300), fbrd(0), ibrd(0), lcrh(0), ifls(0x12),
imsc(0), rawInt(0),
endOnEOT(p.end_on_eot), interrupt(p.interrupt->get()),
intDelay(p.int_delay)
{
}
Tick
Pl011::read(PacketPtr pkt)
{
assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
assert(pkt->getSize() <= 4);
Addr daddr = pkt->getAddr() - pioAddr;
DPRINTF(Uart, " read register %#x size=%d\n", daddr, pkt->getSize());
// use a temporary data since the uart registers are read/written with
// different size operations
//
uint32_t data = 0;
switch(daddr) {
case UART_DR:
data = 0;
if (device->dataAvailable()) {
data = device->readData();
// Since we don't simulate a FIFO for incoming data, we
// assume it's empty and clear RXINTR and RTINTR.
clearInterrupts(UART_RXINTR | UART_RTINTR);
if (device->dataAvailable()) {
DPRINTF(Uart, "Re-raising interrupt due to more data "
"after UART_DR read\n");
dataAvailable();
}
}
break;
case UART_RSR:
data = 0x0; // We never have errors
break;
case UART_FR:
data =
UART_FR_CTS | // Clear To Send
// Given we do not simulate a FIFO we are either empty or full.
(!device->dataAvailable() ? UART_FR_RXFE : UART_FR_RXFF) |
UART_FR_TXFE; // TX FIFO empty
DPRINTF(Uart,
"Reading FR register as %#x rawInt=0x%x "
"imsc=0x%x maskInt=0x%x\n",
data, rawInt, imsc, maskInt());
break;
case UART_CR:
data = control;
break;
case UART_IBRD:
data = ibrd;
break;
case UART_FBRD:
data = fbrd;
break;
case UART_LCRH:
data = lcrh;
break;
case UART_IFLS:
data = ifls;
break;
case UART_IMSC:
data = imsc;
break;
case UART_RIS:
data = rawInt;
DPRINTF(Uart, "Reading Raw Int status as 0x%x\n", rawInt);
break;
case UART_MIS:
DPRINTF(Uart, "Reading Masked Int status as 0x%x\n", maskInt());
data = maskInt();
break;
case UART_DMACR:
warn("PL011: DMA not supported\n");
data = 0x0; // DMA never enabled
break;
default:
if (readId(pkt, AMBA_ID, pioAddr)) {
// Hack for variable size accesses
data = pkt->getUintX(ByteOrder::little);
break;
}
panic("Tried to read PL011 at offset %#x that doesn't exist\n", daddr);
break;
}
pkt->setUintX(data, ByteOrder::little);
pkt->makeAtomicResponse();
return pioDelay;
}
Tick
Pl011::write(PacketPtr pkt)
{
assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
assert(pkt->getSize() <= 4);
Addr daddr = pkt->getAddr() - pioAddr;
DPRINTF(Uart, " write register %#x value %#x size=%d\n", daddr,
pkt->getLE<uint8_t>(), pkt->getSize());
// use a temporary data since the uart registers are read/written with
// different size operations
//
const uint32_t data = pkt->getUintX(ByteOrder::little);
switch (daddr) {
case UART_DR:
if ((data & 0xFF) == 0x04 && endOnEOT)
exitSimLoop("UART received EOT", 0);
device->writeData(data & 0xFF);
// We're supposed to clear TXINTR when this register is
// written to, however. since we're also infinitely fast, we
// need to immediately raise it again.
clearInterrupts(UART_TXINTR);
raiseInterrupts(UART_TXINTR);
break;
case UART_ECR: // clears errors, ignore
break;
case UART_CR:
control = data;
break;
case UART_IBRD:
ibrd = data;
break;
case UART_FBRD:
fbrd = data;
break;
case UART_LCRH:
lcrh = data;
break;
case UART_IFLS:
ifls = data;
break;
case UART_IMSC:
DPRINTF(Uart, "Setting interrupt mask 0x%x\n", data);
setInterruptMask(data);
break;
case UART_ICR:
DPRINTF(Uart, "Clearing interrupts 0x%x\n", data);
clearInterrupts(data);
if (device->dataAvailable()) {
DPRINTF(Uart, "Re-raising interrupt due to more data after "
"UART_ICR write\n");
dataAvailable();
}
break;
case UART_DMACR:
// DMA is not supported, so panic if anyome tries to enable it.
// Bits 0, 1, 2 enables DMA on RX, TX, ERR respectively, others res0.
if (data & 0x7) {
panic("Tried to enable DMA on PL011\n");
}
warn("PL011: DMA not supported\n");
break;
default:
panic("Tried to write PL011 at offset %#x that doesn't exist\n", daddr);
break;
}
pkt->makeAtomicResponse();
return pioDelay;
}
void
Pl011::dataAvailable()
{
/*@todo ignore the fifo, just say we have data now
* We might want to fix this, or we might not care */
DPRINTF(Uart, "Data available, scheduling interrupt\n");
raiseInterrupts(UART_RXINTR | UART_RTINTR);
}
void
Pl011::generateInterrupt()
{
DPRINTF(Uart, "Generate Interrupt: imsc=0x%x rawInt=0x%x maskInt=0x%x\n",
imsc, rawInt, maskInt());
if (maskInt()) {
interrupt->raise();
DPRINTF(Uart, " -- Generated\n");
}
}
void
Pl011::setInterrupts(uint16_t ints, uint16_t mask)
{
const bool old_ints(!!maskInt());
imsc = mask;
rawInt = ints;
if (!old_ints && maskInt()) {
if (!intEvent.scheduled())
schedule(intEvent, curTick() + intDelay);
} else if (old_ints && !maskInt()) {
interrupt->clear();
}
}
void
Pl011::serialize(CheckpointOut &cp) const
{
DPRINTF(Checkpoint, "Serializing Arm PL011\n");
SERIALIZE_SCALAR(control);
SERIALIZE_SCALAR(fbrd);
SERIALIZE_SCALAR(ibrd);
SERIALIZE_SCALAR(lcrh);
SERIALIZE_SCALAR(ifls);
// Preserve backwards compatibility by giving these silly names.
paramOut(cp, "imsc_serial", imsc);
paramOut(cp, "rawInt_serial", rawInt);
}
void
Pl011::unserialize(CheckpointIn &cp)
{
DPRINTF(Checkpoint, "Unserializing Arm PL011\n");
UNSERIALIZE_SCALAR(control);
UNSERIALIZE_SCALAR(fbrd);
UNSERIALIZE_SCALAR(ibrd);
UNSERIALIZE_SCALAR(lcrh);
UNSERIALIZE_SCALAR(ifls);
// Preserve backwards compatibility by giving these silly names.
paramIn(cp, "imsc_serial", imsc);
paramIn(cp, "rawInt_serial", rawInt);
}
} // namespace gem5